WINNER II pdf - Final Report - Cept

WINNER II D1.1.2 V1.2
3.1 WINNER Generic Channel Model
WINNER generic model is a system level model, which can describe arbitrary number of propagation
environment realisations for single or multiple radio links for all the defined scenarios for desired antenna
configurations, with one mathematical framework by different parameter sets. Generic model is a
stochastic model with two (or three) levels of randomness. At first, large scale (LS) parameters like
shadow fading, delay and angular spreads are drawn randomly from tabulated distribution functions.
Next, the small scale parameters like delays, powers and directions arrival and departure are drawn
randomly according to tabulated distribution functions and random LS parameters (second moments). At
this stage geometric setup is fixed and only free variables are the random initial phases of the scatterers.
By picking (randomly) different initial phases, an unlimited number of different realisations of the model
can be generated. When also the initial phases are fixed, the model is fully deterministic.
3.1.1 Modelled parameters
Parameters used in the WINNER II Channel Models have been listed and shortly explained below.
Parameter values are given in a later section, see sub-section 4.4.
The first set of parameters is called large scale (LS) parameters, because they are considered as an
average over a typical channel segment i.e. distance of some tens of wave-lengths. First three of the large
scale parameters are used to control the distributions of delay and angular parameters.
Large Scale Parameters
• Delay spread and distribution
• Angle of Departure spread and distribution
• Angle of Arrival Spread and distribution
• Shadow Fading standard deviation
• Ricean K-factor
Support Parameters
• Scaling parameter for Delay distribution
• Cross-polarisation power ratios
• Number of clusters
• Cluster Angle Spread of Departure
• Cluster Angle Spread of Arrival
• Per Cluster Shadowing
• Auto-correlations of the LS parameters
• Cross-correlations of the LS parameters
• Number of rays per cluster
All of these parameters have been specified from the measurement results or, in some cases, found from
literature. Number of rays per cluster has been selected to be 20 as in [3GPPSCM]. Analysis of the
measurement data for the different parameters has been described in the Part II document of this
deliverable. In the WINNER Channel Models the parameters are assumed not to depend on distance.
Although this assumption is probably not strictly valid, it is used for simplicity of the model. The
parameter values are given in paragraph 4.4 and represent expected values over the applicability range.
In the basic case the Angles of Arrival and Departure are specified as two-dimensional, i.e only azimuth
angles are considered. For the indoor and outdoor-to-indoor cases the angles can also be understood as
solid angles, azimuth and elevation, and the modelling can be performed also as three-dimensional.
3.2 Modelling process
The WINNER Channel Modelling Process is depicted in Figure 3-2. The process is divided into three
phases. The first phase starts from definition of propagation scenarios, which means selection of
environments to be measured, antenna heights, mobility, and other general requirements. Generic model
is needed to know what parameters have to be measured. Planning of measurement campaign can be
started when scenarios and generic model exist. Campaign planning has to be done carefully to take into
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